#include <bits/stdc++.h>
using namespace std;

using ll = int; //         <======== !!!
using vi = vector<ll>;
using ii = pair<ll, ll>;

int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);

	int n;
	ll M;
	cin >> n >> M;

	priority_queue<pair<ll, ii>, vector<pair<ll, ii>>, greater<pair<ll, ii>>>
		pq;
	for (int i = 0, a, b; i < n; ++i)
		cin >> a >> b,
		pq.push({(b + a - 1) / a, {a, b}});
	
	ll done = 9e18, A = 0LL, B = 0LL;
	while (!pq.empty() && done > pq.top().first) {
		A += pq.top().second.first;
		B += pq.top().second.second;
		done = (M + B + A - 1LL) / A;
		pq.pop();
	}

	cout << done << endl;

	return 0;
}